Roland Piquepaille writes "German researchers at the Max Planck Institute are using nanotechnology to take movies of cellular processes. They used Quantum Dots (or QDs) as nano-sized markers to visualize DNA sequences. This new approach is crucial for the development of new cancer drugs. "These Quantum Dots are nano-sized semiconductor crystals a mere ten millionth of a millimeter in diameter that fluoresce in several different colors upon excitation with a laser source. These crystals enabled the researchers to deliver real-time video-clips of signal transmission in the so-called erbB receptor family, important targets for many anti-tumor drugs such as antibodies directed against breast cancer." More details and references are available in this overview including some isolated shots from a movie showing live cells activation."